Identification of Active Edge Sites for Electrochemical H 2 Evolution from MoS 2 Nanocatalysts

American Association for the Advancement of Science (AAAS) - Tập 317 Số 5834 - Trang 100-102 - 2007
Thomas F. Jaramillo1,2, Kristina P. Jørgensen1,2, Jacob Bonde1,2, Jane H. Nielsen1,2, Sebastian Horch1,2, Ib Chorkendorff1,2
1Center for Atomic-scale Materials Design, Department of Physics, Nano-DTU, Technical University of Denmark, DK-2800 Lyngby, Denmark.
2Center for Individual Nanoparticle Functionality, Department of Physics, Nano-DTU, Technical University of Denmark, DK-2800 Lyngby, Denmark.

Tóm tắt

The identification of the active sites in heterogeneous catalysis requires a combination of surface sensitive methods and reactivity studies. We determined the active site for hydrogen evolution, a reaction catalyzed by precious metals, on nanoparticulate molybdenum disulfide (MoS 2 ) by atomically resolving the surface of this catalyst before measuring electrochemical activity in solution. By preparing MoS 2 nanoparticles of different sizes, we systematically varied the distribution of surface sites on MoS 2 nanoparticles on Au(111), which we quantified with scanning tunneling microscopy. Electrocatalytic activity measurements for hydrogen evolution correlate linearly with the number of edge sites on the MoS 2 catalyst.

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Tài liệu tham khảo

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We note that Au atoms along the particle edge also scale with the edge length; however previous experimental and computational studies have shown negligible interaction between the MoS 2 and the support ( 14 15 ) leading us to conclude that such sites would be as inactive as those of the blank samples prepared without MoS 2 deposition.

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This project was supported by the Danish Strategic Research Council. T.F.J. acknowledges an H. C. Ørsted Postdoctoral Fellowship from the Technical University of Denmark. The Center for Individual Nanoparticle Functionality is supported by the Danish National Research Foundation. The Center for Atomic-scale Materials Design is supported by the Lundbeck Foundation.

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American Association for the Advancement of Science (AAAS)

Tập 317 Số 5834

100-102

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